Exemptions

Cotton dust is most prevalent and dangerous when the cotton being used is raw. Cotton that has been washed according to strict guidelines is exempt from some or all of the California cotton dust standards. In order to be exempt, employers must prove that the cotton was washed properly. Washing facilities must be open for inspection to the Chief of the Division of Occupational Safety and Health for inspection.

Medical grade cotton; cotton that has been scoured, bleached, and dyed; and mercerized yarn are exempt from 8 CCR 5190.

High-grade cotton that is considered "low middling light spotted" or better is exempt from everything but medical examinations once it has been washed according to the following guidelines:

• The cotton must be washed on a continuous batt system or rayon rinse system.
• The cotton must be washed with water that is at least 60 degrees Celsius (140 degrees Fahrenheit).
• There must be at least 40 times as much water as cotton fiber.
• Bacteria levels in the water must be controlled to prevent contamination of the cotton.

If cotton of a grade lower than "low middling light spotted" has been washed and bleached, it is not exempt from the standard, but instead has a PEL of 500 micrograms of cotton dust per cubic meter of air instead of 200 micrograms of cotton dust per cubic meter of air during yarn manufacturing operations.

To learn more about Cotton Dust Safety visit our Cal/OSHA Cotton Dust Safety Online Training web page.